July 30 (UPI) — U.S. special envoy Steve Witkoff is slated to travel to Israel on Thursday to discuss conditions in Gaza amid reports of a “humanitarian catastrophe” there.

Witkoff is the United States’ special envoy to the Middle East and has tried to negotiate a lasting cease-fire to end hostilities and enable the delivery of aid to Gazans.

Hamas has thwarted Witkoff’s cease-fire efforts, but he is returning to Israel to get an accurate picture of the situation in Gaza, unnamed U.S. officials told NBC News, Axios and The Jerusalem Post.

Officials with the Integrated Food Security Phase Classification on Tuesday announced a “worst-case scenario of famine” is occurring in Gaza, NBC News reported.

IFSPC officials said evidence indicates “widespread starvation, malnutrition and disease” in Gaza.

U.N. officials also say Gazans are experiencing a humanitarian crisis.

“Palestinians in Gaza are enduring a humanitarian catastrophe of epic proportions,” U.N. Secretary-General Antonio Guterres said in a prepared statement on Tuesday.

“This is not a warning,” Guterres said. “It is a reality unfolding before our eyes.”

He said Gazans need food, water, medicine and fuel that “must flow in waves and without obstruction.’

Israel has begun daily pauses in Gaza to better support the delivery and distribution of humanitarian aid to Gazans, but the daily pauses might end.

Israeli Prime Minister Benjamin Netanyahu on Monday met with a group of ministers to discuss potential actions, including a full resumption of the war and annexing parts of Gaza if Hamas does not release all hostages.

“Israel is making extraordinary efforts to secure the release of the hostages, while applying heavy pressure on Hamas in Gaza,” Israeli Defense Minister Israel Katz said on Wednesday.

“If Hamas does not soon announce the release of the hostages,” Katz added, “it will pay a very heavy price.”

Hamas holds 50 hostages, 28 of whom Israeli officials say likely are dead.

Hamas representatives have told mediators they will not negotiate a cease-fire with Israel until humanitarian assistance resumes in Gaza, The Jerusalem Post reported.

Israeli officials recently rejected Hamas’ demand to release living Hamas fighters in exchange for the bodies of dead hostages.